GHSA-VJJP-V767-CX96
Vulnerability from github – Published: 2026-02-04 18:30 – Updated: 2026-02-04 18:30In the Linux kernel, the following vulnerability has been resolved:
iommu/io-pgtable-arm: fix size_t signedness bug in unmap path
__arm_lpae_unmap() returns size_t but was returning -ENOENT (negative error code) when encountering an unmapped PTE. Since size_t is unsigned, -ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE on 64-bit systems).
This corrupted value propagates through the call chain: __arm_lpae_unmap() returns -ENOENT as size_t -> arm_lpae_unmap_pages() returns it -> __iommu_unmap() adds it to iova address -> iommu_pgsize() triggers BUG_ON due to corrupted iova
This can cause IOVA address overflow in __iommu_unmap() loop and trigger BUG_ON in iommu_pgsize() from invalid address alignment.
Fix by returning 0 instead of -ENOENT. The WARN_ON already signals the error condition, and returning 0 (meaning "nothing unmapped") is the correct semantic for size_t return type. This matches the behavior of other io-pgtable implementations (io-pgtable-arm-v7s, io-pgtable-dart) which return 0 on error conditions.
{
"affected": [],
"aliases": [
"CVE-2026-23067"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-02-04T17:16:17Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/io-pgtable-arm: fix size_t signedness bug in unmap path\n\n__arm_lpae_unmap() returns size_t but was returning -ENOENT (negative\nerror code) when encountering an unmapped PTE. Since size_t is unsigned,\n-ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE\non 64-bit systems).\n\nThis corrupted value propagates through the call chain:\n __arm_lpae_unmap() returns -ENOENT as size_t\n -\u003e arm_lpae_unmap_pages() returns it\n -\u003e __iommu_unmap() adds it to iova address\n -\u003e iommu_pgsize() triggers BUG_ON due to corrupted iova\n\nThis can cause IOVA address overflow in __iommu_unmap() loop and\ntrigger BUG_ON in iommu_pgsize() from invalid address alignment.\n\nFix by returning 0 instead of -ENOENT. The WARN_ON already signals\nthe error condition, and returning 0 (meaning \"nothing unmapped\")\nis the correct semantic for size_t return type. This matches the\nbehavior of other io-pgtable implementations (io-pgtable-arm-v7s,\nio-pgtable-dart) which return 0 on error conditions.",
"id": "GHSA-vjjp-v767-cx96",
"modified": "2026-02-04T18:30:43Z",
"published": "2026-02-04T18:30:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23067"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/374e7af67d9d9d6103c2cfc8eb32abfecf3a2fd8"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/41ec6988547819756fb65e94fc24f3e0dddf84ac"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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